Solo Hi-Flow Cats

[Fatdaddy]

Brand: Solo Performance
Price:$593 (Group buy)

Installation: Moderate (you have to work under the car)
Installation Time: 2 hours (by myself)

Quality: 9 (see comments)
Product Performance: 10 (see comments)
Would you recommend to others?: Yes

Comments: My advance apologies because this is not a totally clean before and after product comparison. More on that in a moment. Anyway, the first comment I want to make is that Steve at Solo Performance is an absolutely top drawer kinda guy. Service doesn't get any better.

As to the product, they are 1st rate. I did have to get shorter mounting bolts for the cat-back flanges. All the bolts in the kit are the same length and they were too long on my car. Not a great crisis but I dinged them one point on quality for that reason. They do create a slight tonal change in the exhaust note. Its most noticed at startup and wot. Its slightly deeper and there is some decel burble. It all sounded good to me and it passed the picky person test. She didn't even notice. I also have a vibrational resonance that was not there before. You only hear it when revving in neutral. This is one of the places where I cannot say for certain it was all due to the cats. My catback is modified with an x-pipe. I also have port matched exhaust manifolds. I'm still chasing that down.

As to performance, they did. My car is tuned by Patrick G. After I added the Hfc's, Patrick tweaked the tune and was able to wring an additional 10hp and 11ft/lbs of torque over my previous setup. Nothing has been adjusted in my tune for O2 sensors and I have never had a cel. Overall, I'm close to 60hp over stock without headers. Not bad. I think they live up to their billing and are a good choice if you choose to go without headers.

[Patrick G]

Those are some really solid gains Mitch. You really have a sleeper on your hands. Your power with the cleaned up exhaust manifolds, Solo cats, and X-pipe is approaching what guys with headers are making. Can't complain about that. :)

[G8V8]

Fatdaddy and Patrick,
Interesting data and very close to the power gains VMS reported (w/o port matched exhaust manifolds). When you talk about these approaching header numbers, are you talking LTs or the shorter headers like the Kooks mids and their cats?

From what I've read the '09.5 pup cats suck about 6 hp. Do you think there is much to be gained with an mid-delete/x-pipe or performance catback replacing a non-pup catted OEM catback ('08)?

Put another way, 59-60 hp gains are reported for Solo cats, R-F intakes, tunes and solo catbacks or mid-muffler and resonator deleted/x-piped '09.5s (pup-cats deleted). For cars without the pup-cats to begin with, would the gains be around 53-54 HP with the total hp numbers being about the same or would the pre-pup-cat cars need the mid-muffler and resonators deleted and x-pipes or a performance catback (Solo, Corsa, Borla, MF) to see these gains? If they do, what do you think the free-flowing catbacks contribute?

[GXPaycheck]

Interesting that the bolts were too long. Mine were a tad too short. Needed another half inch or so.
How did you deal with the drivers side O2 sensor? I couldn't find a way to unclip it and the wires are on the short side.

[Fatdaddy]

... For cars without the pup-cats to begin with, would the gains be around 53-54 HP with the total hp numbers being about the same or would the pre-pup-cat cars need the mid-muffler and resonators deleted and x-pipes or a performance catback (Solo, Corsa, Borla, MF) to see these gains? If they do, what do you think the free-flowing catbacks contribute?

The cars would net similar gains if equiped the same. All of them benefit from a less restrictive exhaust.


... How did you deal with the drivers side O2 sensor? I couldn't find a way to unclip it and the wires are on the short side.

It is very tight up there but I was able to unclip it. It went back together without any problems.

[G8V8]

I guess what I was really looking for was is there a HP difference between Solo catback vs. non-pup-cat OEM midpipe in conjunction with Solo axleback (or OEM axlebacks) vs. non-pup-cat midsection with muffler/resonator deletes and x-pipe added in conjunction with Solo axlebacks (or OEM axlebacks)?